JP2009043555A - Electron type breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve miniaturization, and make power supply from the outside unnecessary in an electron type breaker. <P>SOLUTION: The electron type breaker 1 includes a power supply line 3, a contact 31 to open and close the power supply line 3, a CT 32 installed at respective power supply lines 3, an electric current detecting circuit 41 to detect the electric current, a voltage detecting circuit 42 to detect a voltage, a discrimination part 43 to calculate an electric power amount and to discriminate an overcurrent, a tripping part 44 to trip the contact 31, a communication interface 45 to communicate the electric power amount with the outside, a first power supply device 5 to form the power supply from the CT 32 installed at the power supply line 3, and a second power supply 6 to form the power supply from an interphase voltage. By this constitution, since the first power supply device 5 has only to supply the power supply when the power supply line 3 has a short circuit and a large current flows, the CT 32 may be miniaturized, and miniaturization and cost reduction of the electron type breaker 1 can be achieved. Moreover, supply of power supply from the exterior becomes unnecessary. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic breaker that calculates electric energy.

  2. Description of the Related Art Conventionally, an electronic breaker that detects the current and voltage of a power supply line, calculates the amount of electric power, and displays the used electric power is known. However, this type of electronic breaker is provided with a display unit for each breaker, and because it calculates the amount of electric power and supplies the drive power for the display unit from the outside, it is large and expensive, and wiring is complicated. Become.

  There is also known an electronic breaker that generates power from a current transformer provided in a power supply line, calculates the amount of power using the power supply as a driving power supply, and communicates the calculation result to the outside (see, for example, Patent Document 1). ). FIG. 5 shows one configuration of such an electronic breaker. The electronic breaker 101 includes a power line 103 connected to the commercial power source 102, a contact 131 that opens and closes the power line 103, a current transformer 132 provided in each power line 103, and a current based on the output of the current transformer 132. A current detection circuit 141 for detecting the voltage and a voltage detection circuit 142 for detecting the voltage. The electronic breaker 101 further calculates a power amount based on the current value detected by the current detection circuit 141 and the voltage detected by the voltage detection circuit 142, and determines a determination unit 143 that determines an abnormality such as an overcurrent or a short circuit. The trip part 144 which trips the contact 131 according to the trip signal from the part 143, and the communication interface 145 which communicates electric energy outside are provided. The driving energy for the determination unit 143, the trip unit 144, and the like is supplied from a breaker internal power supply circuit 152 that generates power from the current detected by the current transformer 132.

However, in the electronic breaker 101 disclosed in Patent Document 1, since the current transformer 132 generates power, the current transformer 132 becomes large, and wiring is complicated when supplied from an external power source. .
JP 2002-95152 A

  The present invention has been made in order to solve the above-described conventional problems, and an object thereof is to provide an electronic breaker that is small and does not require external power supply.

  In order to achieve the above object, the invention of claim 1 is directed to a current detection unit that detects a current of each line of a power supply line, a voltage detection unit that detects a voltage between the lines, and a current detected by the current detection unit. And a determination unit that calculates the amount of electric power based on the voltage detected by the voltage detection unit and determines an overcurrent, a tripping device that performs circuit interruption according to a trip signal from the determination unit, and In an electronic breaker having a communication interface for communicating the amount of power to the outside, a first power supply device that generates power from the current of the power supply line, and a second that generates power from the interphase voltage of the power supply line A power supply device, and the two power supply devices supply power to the determination unit, the trip device, and the communication interface.

  According to a second aspect of the present invention, in the electronic breaker according to the first aspect, the first power supply device generates a power source from a current transformer that generates a power source and a rectifier circuit from an output of the current transformer. The second power supply device includes a voltage power supply circuit that generates a power supply by performing AC / DC conversion from the interphase voltage via a step-down circuit, and the current power supply circuit and the voltage power supply. By connecting each output of the circuit, the two outputs complement each other and supply power.

  According to a third aspect of the present invention, in the electronic breaker according to the second aspect, the first power supply device includes a constant voltage power supply circuit in a subsequent stage of the rectifier circuit, and the constant voltage power supply circuit and the step-down circuit are connected to each other. By making the respective output voltages substantially the same, the outputs of the two power supplies are added to supply the power.

  According to a fourth aspect of the present invention, in the electronic breaker according to any one of the first to third aspects, at least one of the determination unit, the trip unit, and a power supply circuit to the communication interface. Has a switching unit that opens and closes the power supply circuit, and the determination unit controls opening and closing of the switching unit.

  According to a fifth aspect of the present invention, in the electronic breaker according to any one of the first to fourth aspects, at least one of the determination unit, the trip unit, and a power supply circuit to the communication interface. Has a charging circuit.

  According to the first aspect of the present invention, the first power supply device that generates power from a current transformer provided in the power supply line and the second power supply device that generates power from the interphase voltage of the power supply line are provided. Therefore, in the normal state, the power is removed from the second power supply device and supplied to the device, the discriminating unit, etc., and when the power line is short-circuited and a large current flows, the power is supplied from the first power supply device. Therefore, the current transformer may be small, and the electronic breaker can be reduced in size and cost. In addition, no external power supply is required, and wiring is not necessary.

  According to the invention of claim 2, by connecting the current power supply circuit and the voltage power supply circuit, the two power supply circuits complement each other to supply the power, so that the power can be supplied stably even in the event of an abnormality.

  According to the invention of claim 3, by aligning the output voltages of the current power supply circuit and the voltage power supply circuit, the outputs of the two power supply circuits can be added and supplied, and each power supply output is not wasted. Each power supply circuit can be reduced in size and cost.

  According to the fourth aspect of the present invention, the maximum value of power consumption can be reduced by selecting the power supply destination by opening and closing the switching unit, so that the two power supply circuits can be reduced in size and cost.

  According to the invention of claim 5, since the charged electric power can be used for the driving electric power of the discriminating section, the tripping section, etc., the size and cost of the two power supply circuits can be reduced. Further, even after the circuit is cut off, it is possible to detect the current and voltage of the power supply line and to communicate with the outside using the charged power.

(First embodiment)
An electronic breaker according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of an electronic breaker. The electronic breaker 1 includes a power line 3 connected to the commercial power source 2, a contact 31 for opening and closing the power line 3, and a current transformer (CURRENT TRANSFORMER, hereinafter abbreviated as CT) 32 provided in each power line 3. , A current detection circuit 41 (current detection unit) for detecting current based on the output of CT32, and a voltage detection circuit 42 (voltage detection unit) for detecting voltage. The electronic breaker 1 further calculates a power amount based on the current value detected by the current detection circuit 41 and the voltage detected by the voltage detection circuit 42, and determines a determination unit 43 that determines abnormality such as overcurrent or short circuit. The trip part 44 (trip device) which trips the contact 31 according to the trip signal from the part 43, and the communication interface 45 which communicates electric energy outside are provided. The electronic breaker 1 includes a first power supply device 5 that supplies drive power to the determination unit 43, the tripping unit 44, and the like, a second power supply device 6, and a constant voltage power supply circuit connected to both power supply devices. 46. The first power supply device 5 includes a current power supply circuit 52 that outputs power from the current detected by the CT 32. The second power supply device 6 includes a voltage power supply circuit 62 that outputs power from the interphase voltage of the power supply line 3.

  The operation of the electronic breaker 1 according to this embodiment will be described. The current detection circuit 41 detects the current of each power supply line 3 by CT 32 and transmits the detected current value data to the determination unit 43. The voltage detection circuit 42 detects the voltage of each power supply line 3 and transmits the detected voltage data to the determination unit 43. The determination unit 43 calculates electric power based on the current value data transmitted from the current detection circuit 41 and the voltage value data transmitted from the voltage detection circuit 42, and determines an abnormality such as an overcurrent or a short circuit. The determination unit 43 communicates the power calculation result to the outside from the communication interface 45, and transmits a trip signal to the trip unit 44 when it is determined that an abnormality such as an overcurrent or a short circuit has occurred. . The trip unit 44 that has received the trip signal trips the contact 31.

  In such an operation of the electronic breaker 1, the drive power for the determination unit 43, the trip unit 44, and the communication interface 45 is normally supplied from the second power supply device 6, but a short circuit occurs between the power supply lines 3. When it occurs, the interphase voltage becomes small, and power cannot be supplied from the second power supply device 6. In this case, since a large current flows through the power supply line 3 due to a short circuit, power is generated and supplied by the current power supply circuit 52 from the current detected by the CT 32.

  Next, supply of power from the first and second power supply devices 5 and 6 will be described with reference to FIG. FIG. 2 shows a power supply path of the electronic breaker 1 of this embodiment. The first power supply device 5 includes a current power supply circuit 52 having a rectifier circuit 51 that rectifies the current detected by the CT 32. The second power supply device 6 includes a voltage power supply circuit 62 having a step-down circuit 61 that steps down the interphase voltage 60.

  In the first power supply device 5, the current detected by the CT 32 is converted into a direct current by the rectifier circuit 51 and converted into a voltage. In the second power supply device 6, the interphase voltage 60 is converted into a direct current by a rectifier circuit (not shown), and is stepped down to a drive voltage of the trip unit 44 by a step-down circuit 61. The outputs of the current power supply circuit 52 and the voltage power supply circuit 62 are connected, and power is supplied from the power supply circuit having the higher voltage. The tripping unit 44 is supplied with power at a voltage depending on the state in which both power supply circuits are connected. The determination unit 43 and the communication interface 45 are supplied with power by being stepped down to a drive voltage by a constant voltage power circuit 46.

  Thus, since the first power supply device 5 only needs to supply power when the power supply line 3 is short-circuited and a large current flows, the CT 32 may be small, and the electronic breaker 1 can be reduced in size and cost. Can be planned. In addition, no external power supply is required, and wiring is not necessary. Further, since the two power supply circuits complement each other by supplying the current power supply circuit 52 and the voltage power supply circuit 62, the power supply can be stably performed even in the event of an abnormality.

(Second Embodiment)
An electronic breaker according to a second embodiment of the present invention will be described with reference to FIG. FIG. 3 shows a power supply path of the electronic breaker. Unlike the electronic breaker according to the first embodiment, the electronic breaker 1 includes a constant voltage power circuit 53 disposed after the rectifier circuit 51 in the current power circuit 52. In the first power supply device 5, the current detected by the CT 32 is converted into a direct current by the rectifier circuit 51 and converted into a voltage, and then the constant voltage power supply circuit 53 causes the voltage power supply circuit 62 of the second power supply device 6. Same voltage as output. Thus, by aligning the output voltages of the current power supply circuit 52 and the voltage power supply circuit 61, the outputs of the two power supply circuits can be added together, and the outputs of the respective power supply circuits are not wasted. The power supply circuit can be reduced in size and cost.

(Third embodiment)
An electronic breaker according to a third embodiment of the present invention will be described with reference to FIG. FIG. 4 shows a power supply path of the electronic breaker. Unlike the electronic breaker according to the first embodiment, the electronic breaker 1 includes switching units 71 to 73 that open and close the power supply to the power supply circuit 7 to the determination unit 43, the trip unit 44, and the communication interface 45. The determination unit 43 controls the opening and closing of the switching units 71 to 73. The electronic breaker 1 also includes a charging circuit 8 that charges drive power for the determination unit 43, the trip unit 44, and the communication interface 45. The power charged by the charging circuit 8 is supplied to a device in which the switching units 71 to 73 are closed.

  The determination unit 43 normally supplies power only to the determination unit 43 by closing the switching unit 71 and opening the switching units 72 and 73. When determining the amount of power to the outside, the determination unit 43 closes the switching unit 73 and opens the switching unit 71 to supply power only to the communication interface 45 to perform communication. After the communication ends, the switching units 71 and 73 return to the original state. The return operation is performed, for example, by the communication interface 45 transmitting an open / close signal to the switching units 71 and 73. In addition, when an overcurrent, a short circuit, or the like occurs, the determination unit 43 closes the switching unit 72 after operating a thyristor (not shown) provided in the trip unit 44 for tripping the contacts. Then, the switching unit 71 is opened, power is supplied only to the tripping unit 44, and the contact is tripped. When the contact is pulled off, the switching unit 71 returns to the closed state. The return operation of the switching unit 71 is performed, for example, when the tripping unit 44 closes the switching unit 71 mechanically in conjunction with the contact tripping operation.

  By controlling the switching units 71 to 73 to open / close as described above, the maximum value of power consumption can be reduced. For example, when the trip unit 44 has a power capacity of 0.3 W, the communication interface 45 has a power capacity of 0.2 W, and the determination unit 43 has a power capacity of 0.1 W, the total power capacity is 0.6 W. However, the maximum power consumption can be reduced to 0.3 W, which is the power capacity of the tripping unit 44, by opening and closing the switching units 71 to 73.

  In this way, the maximum value of power consumption can be reduced by selecting the power supply destination by opening and closing the switching units 71 to 73, so that the two power supply circuits can be reduced in size and cost. In addition, since the power charged in the charging circuit 8 can be used as driving power for the discriminating unit 43, the tripping unit 44, etc., the two power supply circuits can be reduced in size and cost. Further, even after the contact is removed, it is possible to detect the current and voltage of the power supply line and to communicate with the outside using the charged power.

  In addition, this invention is not restricted to the structure of the said various embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. For example, a charging circuit may be provided separately for each of the determination unit 43, the trip unit 44, and the communication interface 45.

The block diagram of the electronic breaker which concerns on the 1st Embodiment of this invention. The figure which shows the power supply path of the same electronic breaker. The figure which shows the power supply path of the electronic breaker which concerns on the 2nd Embodiment of this invention. The figure which shows the power supply path of the electronic breaker which concerns on the 3rd Embodiment of this invention. The block diagram of the conventional electronic breaker.

Explanation of symbols

1 Electronic breaker 3 Power line 32 CT (current transformer)
41 Current detection circuit (current detection unit)
42 Voltage detection circuit (voltage detection unit)
43 discriminating part 44 tripping part (tripping device)
45 communication interface 46 constant voltage power supply circuit 5 first power supply device 51 rectifier circuit 52 current power supply circuit 6 second power supply device 61 step-down circuit 62 voltage power supply circuit 7 power supply circuits 71, 72, 73 switching unit 8 charging circuit

Claims (5)

A current detector for detecting the current of each line of the power supply line, a voltage detector for detecting the voltage between the lines,
Based on the current detected by the current detection unit and the voltage detected by the voltage detection unit, a power is calculated and a determination unit for determining an overcurrent, and a circuit according to a trip signal from the determination unit In an electronic breaker comprising a tripping device that performs shut-off and a communication interface that communicates the amount of power to the outside,
A first power supply device that generates power from the current of the power supply line;
A second power supply device that generates power from the interphase voltage of the power supply line,
An electronic breaker characterized in that power is supplied to the discriminator, tripping device, and communication interface by the two power supply devices. The first power supply device includes a current transformer that generates power, and a current power circuit that generates power from the output of the current transformer via a rectifier circuit,
The second power supply device includes a voltage power supply circuit that generates a power supply by performing AC / DC conversion from the interphase voltage via a step-down circuit,
2. The electronic breaker according to claim 1, wherein the outputs of the current power supply circuit and the voltage power supply circuit are connected to supply power complementarily with each other by two outputs. The first power supply device has a constant voltage power supply circuit at a subsequent stage of the rectifier circuit,
3. The electronic breaker according to claim 2, wherein the power supply is supplied by adding the outputs of the two power supplies by making the output voltages of the constant voltage power supply circuit and the step-down circuit substantially the same. At least one of the determination unit, the trip unit, and the power supply circuit to the communication interface has a switching unit that opens and closes the power supply circuit,
The electronic breaker according to any one of claims 1 to 3, wherein the determination unit controls opening and closing of the switching unit.   5. The electronic device according to claim 1, wherein at least one of the determination unit, the trip unit, and a power supply circuit to the communication interface includes a charging circuit. 6. Formula breaker.

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